THE FUNGI 377 
which are often tangled in mounts prepared by transferring the 
mycelium with a forceps or needle. These may be prepared by 
the Henrici method as follows: Clean large rectangular cover 
glasses and deposit a drop of de Khotinsky cement or melted 
sealing wax on each end; spreading it out with a small hot iron 
file to form a layer 5 mm. wide. Heat a slide in a flame and 
place the cover glass on it with the cement side down. The slide 
should be just hot enough to soften the cement rather than to 
liquefy it. The culture chamber thus prepared has a space 
between the cover slip and slide about 1 mm. deep. Melt a tube 
of Czapek’s agar, cool and inoculate with spores of the mold to be 
examined. With asterile pipette transfer some of the inoculated 
agar to the edge of the cover glass and allow it to run under until 
part of the space has been filled. ‘The slides are then placed in a 
clean glass staining jar containing moistened filter paper in the 
bottom and the lid sealed with vaseline, ‘and the slides incubated 
until growth has occurred. 
OrRDER ZYGOMYCETALES 
THe Biack Breap Mo.p.—Ruizopus Nicricans (Mucor 
stolonifer), commonly known as “Black Mold” or ‘‘Black Bread 
Mold,” is frequently found on bread, jellies, syrups, acetic 
pharmaceutical extracts and other substrata, where it forms a 
dense thready mycelium bearing numerous black, tiny spore cases. 
The source of this mold is the spores, which are found in the air 
or water with which the attacked substratum isincontact. Each 
of these, upon germinating, sprouts out and forms a vegetative 
mycelium consisting of three kinds of hyphe, viz.: rhizoidal or 
submerged hyphae, sporangiophores or aerial hyphe and stolontferous 
hyphe. The branching rhizoidal hyphe penetrate the substratum 
and secrete a diastatic ferment that changes the water insoluble 
carbohydrate materials into a soluble sugar which passes into 
solution and is absorbed by their walls. ‘This, upon entering the 
hyphez, is converted into protoplasm, and so the mold increases in 
size. Sporangiophores or aerial hyphz arise vertically or 
obliquely from a bulged-out common base of the rhizoidal hyphz. 
Each of these when mature bears upon its summit a spheroidal 
sporangium containing numerous small, brownish, multinucleate 
